What bats do we have in Tayside?

There are over 13,000 species of bats around the world. Eighteen of these live in Britain and just five of these species live with us in Tayside.

All species of bat in Britain are insectivorous which means they only eat insects.

Because of this they do a very important job in pest control - not only around our houses but on fields and crops too.

Scroll on below to read about the Tayside Bats.

Brown long-eared bat in tree (©Hugh Clark~Bat Conservation Trust)

Common pipistrelles (Pipistrellus pipistrellus) Soprano pipistrelles (Pipistrellus pygmaeus)

The Common pipistrelle and Soprano pipistrelle were once assumed to be one species, but research in the late 1990's and early 2000's proved they are two distinct but very similar species.

The common pipistrelle is actually more common further south than in Tayside but there are still a lot of them around. The soprano pipistrelle is more common up here in Scotland than down south and tends to form the biggest maternity roosts of all our bat species.

Both pipistrelle species weigh about 4-6g and are the bat you are most likely to see in our evening skies. They come out at dusk and are the spitfires of the bat world - flying fast, darting in and out of treelines and inbetween houses catching fast agile tiny insects. They look much bigger flying than on when you see them close up, as their wings are very big.

Common pipistrelle's faces often have a very dark mark around the eyes and mouth and their fur is medium to dark brown, whereas Soprano pipistrelles are usually very pinky around the face and their fur can be bit lighter. However, their colouring is not the best way to tell the difference between the species as they can look very similar.

Some people look at the venation of the wings to tell pipistrelle species apart but the easiest way to tell the difference between the two species is with a bat detector - common pipistrelles tend to echolocate between 40-50kHz and soprano pipistrelles between 50-60kHz.

These bats are very adaptable and live happily alongside us, often without us knowing! Like all our bats, they do not chew or make nests, and will often roost snugly between the slates and sarking of our roofs all day, and dart out at dusk - if you blink you miss them!

They mostly live in small groups, except during the summer (around May to August in Tayside) where the females will come together to form large maternity colonies. This means they can deliver and raise their babies together in warmth and safety - they sleep, nurse and groom their babies during the day and leave them all together to go out and hunt at night, coming back to suckle them if necessary.

The Common pipistrelles will form maternity colonies of an average of 75 bats and will often move around different roosts. Sometimes they share with Soprano pipistrelles who behave slightly differently - they tend to stay put in one roost over the summer and have much larger colonies with an average of 200 bats but they can be much larger and occasionally number 500+ or even thousands.

But, after their babies have grown up at the end of summer, they disperse into smaller groups and move into other transitional roosts.

Common pipistrelle (© Rosie Corner & Bat Conservation Trust

Pipistrelle in flight ©Hugh Clark-Bat Conservation Trust

Brown long eared bats (Plecotus auritus

These are arguably our most charismatic bats with their long ears! They are about double the size of the pipistrelles, at about 6-12g and tAheir ears are nearly as long as their body. They eat a diet of mostly moths but also beetles, earwigs and flies as well.

The reason why they have such big ears is because of they are specialised to listen to low frequency prey-generated sounds - like the flutter of a moth's wing!

They also have good eyesight and use their ears and eyes more for hunting then other species of bats, who use echolocation as a primary method. This might be because moths have evolved a method of "blocking" a bats echolocation, so brown long eared bats have evolved to switch off their hunting echolocation and use sight and sound instead.

As they hunt slow moving moths or stationary spiders they don't need to fly so fast, and their large ears create drag that slows them down, so their flight is slow, twisty and hovering, more like a chinook helicoptor than a spitfire!

Brown long eared bats also like to share our houses with us, but prefer large country houses with large attics near to lots of trees. This is because they don't emerge straight out at dusk, but fly around inside the attic until its completely dark. When they do come out they tend to hunt under trees and in thick vegetation so its very hard to spot them flying around.

Also, if you have a bat detectors they are called the "whispering bat" for good reason - you have to be really close to one before you hear the echolocation call - whereas a pipistrelle will deafen you at the same distance!

Brown long eared bat © Jean Oudney

Brown long eared bat hunting © Hugh Clark & Bat Conservation Trust

Natterer's bat (Myotis nattereri)

Like the brown long eared bats, Natterer's bats are also more difficult to see because they come out after dark and like to hunt amongst trees. They like to roost in old buildings with large timber beams, such as churches, barns and castles but will also use bridges and trees as well.

They are about the same size as brown long eared bats but their ears are much shorter and a different shape. Their faces are quite pinky and they have a characteristic fringe of bristles on the edge of their tail membrane.

They also fly quite slowly and "glean" their prey from walls and trees and will also hunt moths, but not as often as brown long eared bats.

Because Natterer's bats are rare and our population is of international importance, and also that they are easily disturbed by humans, they are highly protected under law - both their roosts and the bats themselves. This is especially important to remember when carrying out any kind of timber treatment as they like to roost in crevices in the wooden beams and they could be poisoned by the chemicals.

031 - Natterer's bat found high in the mountains in Glenshee bat box checks.jpg

Daubenton's bats (Myotis daubentonii)

If you are around a still piece of river or loch about an hour after sunset, look out for a bat skimming the top of the water as it hunts low over the water. If you shine a torch on them and you can see a grey belly, it is a Daubenton's bat.

These bats are about the same size as brown long eared bats and Natterer's bats with a pinkish face and very plush dark fur. One of the ways to identify a Daubenton's bat is by their huge feet - used to catch the insects hovering on top of the water. They will often use their tail as well to scoop up the insect.

Daubenton's bats like to live close to the water under bridges or culverts, in trees and occasionally in houses close to the water. In winter they like to hibernate underground in tunnels or mines - in Tayside we don't have many tunnels or mines so its possible they use large trees or bridges with deep crevices to hibernate in as an alternative. Like other bats its important for them to have a constant, slightly moist low temperature that does not disturb them.

If you have a bat detector and you listen to Daubenton's bats, you will hear a series of rapid clicks like a machine gun. The reason they prefer still water is that the ripples and waves of rough water interfere with their echolocation. You will often see pipistrelles hunting over the water but they tend to stay much higher over the water and have a swooping, darting way of flying compared to the low steady sweep of the Daubenton's bats.

Tayside Bat Group